RESUMO
The interpretation of odds ratios (OR) as prevalence ratios (PR) in cross-sectional studies have been criticized since this equivalence is not true unless under specific circumstances. The logistic regression model is a very well known statistical tool for analysis of binary outcomes and frequently used to obtain adjusted OR. Here, we introduce the prLogistic for the R statistical computing environment which can be obtained from The Comprehensive R Archive Network, https://cran.r-project.org/package=prLogistic. The package prLogistic was built to assist the estimation of PR via logistic regression models adjusted by delta method and bootstrap for analysis of independent and correlated binary data. Two applications are presented to illustrate its use for analysis of independent observations and data from clustered studies.
Assuntos
Modelos Logísticos , Estudos Transversais , Razão de Chances , PrevalênciaRESUMO
BACKGROUND: Record linkage is the process of identifying and combining records about the same individual from two or more different datasets. While there are many open source and commercial data linkage tools, the volume and complexity of currently available datasets for linkage pose a huge challenge; hence, designing an efficient linkage tool with reasonable accuracy and scalability is required. METHODS: We developed CIDACS-RL (Centre for Data and Knowledge Integration for Health - Record Linkage), a novel iterative deterministic record linkage algorithm based on a combination of indexing search and scoring algorithms (provided by Apache Lucene). We described how the algorithm works and compared its performance with four open source linkage tools (AtyImo, Febrl, FRIL and RecLink) in terms of sensitivity and positive predictive value using gold standard dataset. We also evaluated its accuracy and scalability using a case-study and its scalability and execution time using a simulated cohort in serial (single core) and multi-core (eight core) computation settings. RESULTS: Overall, CIDACS-RL algorithm had a superior performance: positive predictive value (99.93% versus AtyImo 99.30%, RecLink 99.5%, Febrl 98.86%, and FRIL 96.17%) and sensitivity (99.87% versus AtyImo 98.91%, RecLink 73.75%, Febrl 90.58%, and FRIL 74.66%). In the case study, using a ROC curve to choose the most appropriate cut-off value (0.896), the obtained metrics were: sensitivity = 92.5% (95% CI 92.07-92.99), specificity = 93.5% (95% CI 93.08-93.8) and area under the curve (AUC) = 97% (95% CI 96.97-97.35). The multi-core computation was about four times faster (150 seconds) than the serial setting (550 seconds) when using a dataset of 20 million records. CONCLUSION: CIDACS-RL algorithm is an innovative linkage tool for huge datasets, with higher accuracy, improved scalability, and substantially shorter execution time compared to other existing linkage tools. In addition, CIDACS-RL can be deployed on standard computers without the need for high-speed processors and distributed infrastructures.
Assuntos
Conjuntos de Dados como Assunto , Armazenamento e Recuperação da Informação , Registro Médico Coordenado , Algoritmos , Estudos de Coortes , Humanos , Sistemas Computadorizados de Registros MédicosRESUMO
In large prospective cohort studies, accumulation of covariate information and follow-up data make up the majority of the cost involved in the study. This might lead to the study being infeasible when there are some expensive variables and/or the event is rare. Prentice (Biometrika 73(1):1-11, 1986) proposed the case-cohort study for time to event data to tackle this problem. There has been extensive research on the analysis of univariate and clustered failure time data, where the clusters are formed among different individuals under case-cohort sampling scheme. However, recurrent event data are quite common in biomedical and public health research. In this paper, we propose case-cohort sampling schemes for recurrent events. We consider a multiplicative rates model for the recurrent events and propose a weighted estimating equations approach for parameter estimation. We show that the estimators are consistent and asymptotically normally distributed. The proposed estimator performed well in finite samples in our simulation studies. For illustration purposes, we examined the association between prior occurrence of measles on acute lower respiratory tract infections (ALRI) among young children in Brazil.
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Estudos de Coortes , Recidiva , Simulação por Computador , Humanos , Estudos Prospectivos , Análise de RegressãoRESUMO
RATIONALE: Exposures to geohelminths during gestation or early childhood may reduce risk of wheezing illness/asthma and atopy during childhood in tropical regions. OBJECTIVES: To investigate the effect of maternal and early childhood geohelminths on development of wheeze/asthma and atopy during the first 5 years of life. METHODS: A cohort of 2,404 neonates was followed to 5 years of age in a rural district in coastal Ecuador. Data on wheeze were collected by questionnaire and atopy was measured by allergen skin prick test reactivity to 10 allergens at 5 years. Stool samples from mothers and children were examined for geohelminths by microscopy. MEASUREMENTS AND MAIN RESULTS: A total of 2,090 (86.9%) children were evaluated at 5 years. Geohelminths were observed in 45.5% of mothers and in 34.1% of children by 3 years. Wheeze and asthma were reported for 12.6% and 5.7% of children, respectively, whereas 14.0% had skin test reactivity at 5 years. Maternal geohelminths were associated with an increased risk of wheeze (adjusted odds ratio, 1.41; 95% confidence interval, 1.06-1.88), whereas childhood geohelminths over the first 3 years of life were associated with reduced risk of wheeze (adjusted odds ratio, 0.70; 95% confidence interval, 0.52-0.96) and asthma (adjusted odds ratio, 0.60; 95% confidence interval, 0.38-0.94) but not skin prick test reactivity. The effects on wheeze/asthma were greatest with later age of first infection, were observed only in skin test-negative children, but were not associated with parasite burden or specific geohelminths. CONCLUSIONS: Although maternal exposures to geohelminths may increase childhood wheeze, childhood geohelminths during the first 3 years may provide protection through a nonallergic mechanism. Registered as an observational study (ISRCTN41239086).
Assuntos
Asma/imunologia , Helmintíase/imunologia , Helmintos/imunologia , Exposição Materna/efeitos adversos , Adulto , Fatores Etários , Alérgenos/imunologia , Animais , Asma/prevenção & controle , Pré-Escolar , Estudos de Coortes , Países em Desenvolvimento , Equador , Eczema/imunologia , Eczema/prevenção & controle , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Sons Respiratórios/imunologia , Medição de Risco , Fatores de TempoRESUMO
BACKGROUND: Maternal geohelminth infections during pregnancy may protect against allergy development in childhood. OBJECTIVE: We sought to investigate the effect of maternal geohelminths on the development of eczema, wheeze, and atopy during the first 3 years of life. METHODS: A cohort of 2404 neonates was followed to 3 years of age in a rural district in coastal Ecuador. Data on wheeze and eczema were collected by means of questionnaire and physical examination at 13, 24, and 36 months of age. Atopy was measured based on skin prick test (SPT) reactivity to 9 allergens at 36 months. Maternal stool samples were examined for geohelminths by microscopy. Data on potential confounders was collected after birth by questionnaire. RESULTS: Geohelminths were observed in 45.9% of mothers. Eczema and wheeze were reported for 17.7% and 25.9%, respectively, of 2069 (86.1%) children with complete follow-up to 3 years, and allergen SPT reactivity to any allergen was present in 17.2% and to house dust mite in 8.7%. Maternal geohelminth infections were not significantly associated with eczema (adjusted odds ratio [OR], 1.26; 95% CI, 0.98-1.61), wheeze (adjusted OR, 1.02; 95% CI, 0.82-1.27), and SPT reactivity to any allergen (adjusted OR, 0.79; 95% CI, 0.61-1.01). In subgroup analyses maternal geohelminths were associated with a significantly reduced risk of SPT reactivity to mite and other perennial allergens, and maternal ascariasis was associated with an increased risk of eczema and reduced risk of SPT reactivity to all allergens. CONCLUSION: Our data do not support a protective effect of maternal infections with geohelminth parasites during pregnancy against the development of eczema and wheeze in early childhood, although there was evidence in subgroup analyses for a reduction in SPT reactivity to house dust mites and perennial allergens.
Assuntos
Helmintíase/complicações , Hipersensibilidade/epidemiologia , Hipersensibilidade/etiologia , Exposição Materna/efeitos adversos , Alérgenos/imunologia , Animais , Pré-Escolar , Eczema/epidemiologia , Eczema/etiologia , Feminino , Seguimentos , Helmintíase/parasitologia , Humanos , Lactente , Recém-Nascido , Masculino , Razão de Chances , Avaliação de Resultados da Assistência ao Paciente , Gravidez , Pyroglyphidae/imunologia , Sons Respiratórios/etiologia , Fatores de RiscoRESUMO
BACKGROUND: Immunologists often measure several correlated immunological markers, such as concentrations of different cytokines produced by different immune cells and/or measured under different conditions, to draw insights from complex immunological mechanisms. Although there have been recent methodological efforts to improve the statistical analysis of immunological data, a framework is still needed for the simultaneous analysis of multiple, often correlated, immune markers. This framework would allow the immunologists' hypotheses about the underlying biological mechanisms to be integrated. RESULTS: We present an analytical approach for statistical analysis of correlated immune markers, such as those commonly collected in modern immuno-epidemiological studies. We demonstrate i) how to deal with interdependencies among multiple measurements of the same immune marker, ii) how to analyse association patterns among different markers, iii) how to aggregate different measures and/or markers to immunological summary scores, iv) how to model the inter-relationships among these scores, and v) how to use these scores in epidemiological association analyses. We illustrate the application of our approach to multiple cytokine measurements from 818 children enrolled in a large immuno-epidemiological study (SCAALA Salvador), which aimed to quantify the major immunological mechanisms underlying atopic diseases or asthma. We demonstrate how to aggregate systematically the information captured in multiple cytokine measurements to immunological summary scores aimed at reflecting the presumed underlying immunological mechanisms (Th1/Th2 balance and immune regulatory network). We show how these aggregated immune scores can be used as predictors in regression models with outcomes of immunological studies (e.g. specific IgE) and compare the results to those obtained by a traditional multivariate regression approach. CONCLUSION: The proposed analytical approach may be especially useful to quantify complex immune responses in immuno-epidemiological studies, where investigators examine the relationship among epidemiological patterns, immune response, and disease outcomes.
Assuntos
Alergia e Imunologia , Asma/diagnóstico , Epidemiologia , Hipersensibilidade Imediata/diagnóstico , Biomarcadores/metabolismo , Pesquisa Biomédica , Brasil/epidemiologia , Criança , Simulação por Computador , Citocinas/metabolismo , Interpretação Estatística de Dados , Humanos , Imunoglobulina E/sangue , Sistemas Integrados e Avançados de Gestão da Informação , Avaliação de Resultados em Cuidados de Saúde/métodos , Valor Preditivo dos Testes , Prognóstico , Equilíbrio Th1-Th2RESUMO
BACKGROUND: It has been proposed that improved hygiene and reduced experience of infections in childhood influences the development of allergic diseases. The mechanisms by which the hygiene operates are not well established but are underpinned by two apparently incompatible immunologic paradigms, the balance of TH1 versus TH2 cytokines and IL-10-mediated regulation of TH2 cytokines. OBJECTIVE: This study defined immunologic phenotypes with the use of latent class analysis and investigated their associations with environmental factors, markers of allergy and asthma, in a Latin American population. METHODS: We studied 1127 children living in urban Brazil. Data on wheeze and environmental exposures were collected with standardized questionnaires. Atopy was measured by specific IgE in serum and skin prick test reactivity to aeroallergens. Cytokines were measured in culture after the stimulation of peripheral blood leukocytes with mitogen. Infections with pathogens were assessed by serology and stool examinations. Children were classified as having high or low burden of infection. Latent class analysis was used to identify immune phenotypes on the basis of cytokine production. Logistic regression was used to evaluate the adjusted effects of environment and burden of infection on the immunologic phenotypes and the effect of the phenotypes on atopy and asthma. RESULTS: Three phenotypes were identified, labeled underresponsive, intermediate, and responsive. Children of more educated mothers, living in improved environmental conditions, and with a low burden of infection were significantly more likely to have the responsive phenotype. The responsive phenotype was significantly associated with an increased prevalence of atopy but not asthma. CONCLUSION: Our findings contribute to a better understanding of the immune mechanisms by which the hygiene hypothesis operates in urban Latin America.
Assuntos
Asma/imunologia , Exposição Ambiental , Hipótese da Higiene , Hipersensibilidade Imediata/imunologia , Adolescente , Alérgenos/imunologia , Asma/epidemiologia , Asma/patologia , Brasil/epidemiologia , Criança , Citocinas/imunologia , Meio Ambiente , Feminino , Humanos , Higiene , Hipersensibilidade Imediata/epidemiologia , Hipersensibilidade Imediata/patologia , Imunoglobulina E/imunologia , Imunofenotipagem , Interleucina-10/imunologia , Masculino , Prevalência , Testes Cutâneos , Inquéritos e Questionários , Equilíbrio Th1-Th2 , População UrbanaRESUMO
BACKGROUND: Helminth infections are associated with protection against allergies. It is postulated that IL-10 production after helminth infection suppresses skin hypersensitivity and increases IgG4 production, protecting against allergies. OBJECTIVE: We aimed to determine whether IL10 polymorphisms are associated with helminth infection and the risk of wheeze and allergy. METHODS: Twelve IL10 single nucleotide polymorphisms were genotyped in 1353 children aged 4 to 11 years living in a poor urban area in Salvador, Brazil. Wheezing status, Ascaris lumbricoides and Trichuris trichiura infection, IL-10 production by peripheral blood leukocytes stimulated with A lumbricoides extract, serum total IgE levels, specific IgE levels, skin prick test responses to common aeroallergens, and IgG4 and IgE anti-A lumbricoides antibody levels were measured in all children. Association tests were performed by using logistic or linear regression when appropriate, including sex, age, helminth infection, and principal components for ancestry informative markers as covariates by using PLINK. RESULTS: Allele G of marker rs3024496 was associated with the decreased production of IL-10 by peripheral blood leukocytes in response to A lumbricoides stimulation. Allele C of marker rs3024498 was negatively associated with helminth infection or its markers. Marker rs3024492 was positively associated with the risk of atopic wheeze, total IgE levels, and skin prick test responses to cockroach. CONCLUSIONS: Our findings suggest that IL10 polymorphisms might play a role in the production of IL-10, helminth infection, and allergy. We hypothesize that polymorphisms related to protection against helminths, which would offer an evolutionary advantage to subjects in the past, might be associated with increased risk of allergic diseases.
Assuntos
Asma/epidemiologia , Asma/etiologia , Helmintíase/complicações , Interleucina-10/biossíntese , Interleucina-10/genética , Polimorfismo Genético , Sons Respiratórios/etiologia , Adolescente , Alelos , Brasil/epidemiologia , Criança , Pré-Escolar , Feminino , Ordem dos Genes , Ligação Genética , Genótipo , Humanos , Lactente , Desequilíbrio de Ligação , Masculino , Polimorfismo de Nucleotídeo Único , População UrbanaRESUMO
Studies analyzing relations between cardiovascular diseases (CVDs) and environmental aspects in Latin American cities are relatively recent and limited, since most of them are conducted in high-income countries, analyzing mortality outcomes, and comprising large areas. This research focuses on adults with diabetes and/or hypertension under clinical follow-up who live in deprived areas. At the individual level we evaluated sociodemographic and cardiovascular risk factors from patient's records, and at the neighborhood level, socioeconomic conditions from census data. A multilevel analysis was carried out to study CVD. More women than men were under clinical follow-up, but men had higher frequency, higher odds, and shorter time to CVD diagnosis. Multilevel analysis showed that residing in neighborhoods with worst socioeconomic conditions leads to higher odds of CVDs, even after controlling for individual variables: OR (CI95%) of CVD in quartile 2 (Q2) 3.9 (1.2-12.1); Q3 4.0 (1.3-12.3); Q4 2.3 (0.7-8.0) (vs. highest socioeconomic level quartile). Among individuals living in unequal contexts, we found differences in CVD, which makes visible inequalities within inequalities. Differences between women and men should be considered through a gender perspective.
Assuntos
Doenças Cardiovasculares , Adulto , Doenças Cardiovasculares/epidemiologia , Cidades , Feminino , Humanos , América Latina/epidemiologia , Masculino , Análise Multinível , Características de Residência , Fatores SocioeconômicosRESUMO
Emerging evidence suggests that vicarious racial experiences of discrimination may negatively influence child health. Few studies have focus on childhood asthma symptoms and potential moderators of such relationship. METHODS: We used two population-based cross-sectional studies from the Social Change Allergy and Asthma in Latin America project in Salvador, Brazil. A total of 1003 children and mothers interviewed in 2006 were included, of whom 873 were reached again in 2013. Vicarious racial discrimination was assessed in mothers by applying the Experiences of Discrimination scale. Data on wheeze and environmental exposures were collected with standardized questionnaires. Levels of allergen-specific IgE were measured to identify atopy. Generalized estimating equations were used to estimate the association between maternal discrimination and wheezing and asthma phenotypes. Interaction terms were evaluated to identify whether mothers' mental health and family social support modified such associations. RESULTS: Children whose mothers reported racial discrimination had greater odds of have asthma symptoms (OR 1.75; 95% CI 1.15-2.67) and non-atopic asthma (OR 1.92; 95% CI 1.09-3.40). When we considered effect modification by social support, we found a higher ORs when the level of social support was lower (OR 2.43; 95% IC 1.19-4.97) than when the level of social support was higher (OR 1.12; CI 0.64-1.96). CONCLUSION: Maternal discrimination was associated with asthma symptoms and with non-atopic phenotype among their children. Enjoying wider social support network appears to buffer the effect on asthmatic symptoms. Intervention on childhood asthma needs to incorporate strategies that target the family.
Assuntos
Asma , Hipersensibilidade Imediata , Racismo , Adolescente , Criança , Estudos Transversais , Humanos , Hipersensibilidade Imediata/diagnóstico , Racismo/psicologia , Sons RespiratóriosRESUMO
BACKGROUND: Cardiovascular disease (CVD) has a disproportionate effect on mortality among the poorest people. We assessed the impact on CVD and all-cause mortality of the world's largest conditional cash transfer, Brazil's Bolsa Família Programme (BFP). METHODS: We linked administrative data from the 100 Million Brazilian Cohort with BFP receipt and national mortality data. We followed individuals who applied for BFP between 1 January 2011 and 31 December 2015, until 31 December 2015. We used marginal structural models to estimate the effect of BFP on all-age and premature (30-69 years) CVD and all-cause mortality. We conducted stratified analyses by levels of material deprivation and access to healthcare. We checked the robustness of our findings by restricting the analysis to municipalities with better mortality data and by using alternative statistical methods. RESULTS: We studied 17â981â582 individuals, of whom 4â855â324 were aged 30-69 years. Three-quarters (76.2%) received BFP, with a mean follow-up post-award of 2.6 years. We detected 106â807 deaths by all causes, of which 60â893 were premature; and 23â389 CVD deaths, of which 15â292 were premature. BFP was associated with reductions in premature all-cause mortality [hazard ratio (HR) = 0.96, 95% CI = 0.94-0.98], premature CVD (HR = 0.96, 95% CI = 0.92-1.00) and all-age CVD (HR = 0.96, 95% CI = 0.93-1.00) but not all-age all-cause mortality (HR = 1.00, 95% CI = 0.98-1.02). In stratified and robustness analyses, BFP was consistently associated with mortality reductions for individuals living in the two most deprived quintiles. CONCLUSIONS: BFP appears to have a small to null effect on premature CVD and all-cause mortality in the short term; the long-term impact remains unknown.
Assuntos
Doenças Cardiovasculares , Pobreza , Humanos , Brasil/epidemiologiaRESUMO
Allergic and other immune-mediated diseases are complex disease states determined by interplay between host genetics and environmental factors. Environmental changes such as fewer infections and reduced exposure to microbial products have been suggested to have led to insufficient regulation of Th1 and Th2 immune responses, causing an increased incidence of inflammatory diseases. The objective of the present study was to investigate the effect of poor living environmental conditions on mitogen-induced production of cytokines (Th1 and Th2) by peripheral blood leukocytes in children living in urban Brazil and investigate the role of IL-10 in modifying this effect. Our data showed that the proportion of children producing Th1 and Th2 cytokines was lower among those with poor living conditions and that this finding was stronger in children producing IL-10. These results provide a possible biologic explanation for the temporal trends of increasing risk of inflammatory diseases observed in populations living in affluent countries.
Assuntos
Citocinas/metabolismo , Habitação , Interleucina-10/farmacologia , Células Th1/metabolismo , Células Th2/metabolismo , Brasil/epidemiologia , Células Cultivadas , Criança , Pré-Escolar , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Humanos , Hipersensibilidade/epidemiologia , Hipersensibilidade/imunologia , Masculino , Fatores de Risco , Fatores SocioeconômicosRESUMO
Helminth infections have been associated with protection against allergy and autoimmune diseases. We investigated the effects of chronic infections with Ascaris lumbricoides and Trichuris trichiura (measured twice over a 5-year period) on cytokine and antibody responses. We collected blood from 1,060 children aged 4 to 11 years living in a poor urban area of Brazil and measured Th1 (gamma interferon [IFN-gamma]) and Th2 (interleukin-5 [IL-5] and IL-13) cytokines and the regulatory cytokine IL-10 in unstimulated and stimulated (with mitogen or A. lumbricoides antigens) cultures of peripheral blood leukocytes and levels of total IgE and anti-A. lumbricoides IgG4 and IgE in serum. Intestinal helminth infections were associated with an increased proportion of children producing IL-5 in response to A. lumbricoides and producing IL-10 spontaneously, especially among coinfected and chronically infected children. Helminth infections were associated with a generalized suppression of cytokine responses to mitogen. Levels of total IgE and anti-A. lumbricoides IgG4 and IgE were especially elevated in chronically infected children. In conclusion, intestinal helminth infections were associated with a typical Th2 immune response profile and with the induction of immune hyporesponsiveness that was associated with greater frequencies of the production of spontaneous IL-10.
Assuntos
Ascaríase/imunologia , Ascaris lumbricoides/imunologia , Tricuríase/imunologia , Trichuris/imunologia , Animais , Anticorpos Anti-Helmínticos/sangue , Anticorpos Anti-Helmínticos/imunologia , Criança , Pré-Escolar , Feminino , Humanos , Imunidade Humoral/imunologia , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Interferon gama/sangue , Interferon gama/imunologia , Interleucina-10/sangue , Interleucina-10/imunologia , Interleucina-13/sangue , Interleucina-13/imunologia , Interleucina-5/sangue , Interleucina-5/imunologia , MasculinoRESUMO
BACKGROUND: The causation of asthma is poorly understood. Risk factors for atopic and non-atopic asthma may be different. This study aimed to analyze the associations between markers of poverty, dirt and infections and wheezing in atopic and non-atopic children. METHODS: 1445 children were recruited from a population-based cohort in Salvador, Brazil. Wheezing was assessed using the ISAAC questionnaire and atopy defined as allergen-specific IgE ≥ 0.70 kU/L. Relevant social factors, environmental exposures and serological markers for childhood infections were investigated as risk factors using multivariate multinomial logistic regression. RESULTS: Common risk factors for wheezing in atopic and non-atopic children, respectively, were parental asthma and respiratory infection in early childhood. No other factor was associated with wheezing in atopic children. Factors associated with wheezing in non-atopics were low maternal educational level (OR 1.49, 95% CI 0.98-2.38), low frequency of room cleaning (OR 2.49, 95% CI 1.27-4.90), presence of rodents in the house (OR 1.48, 95% CI 1.06-2.09), and day care attendance (OR 1.52, 95% CI 1.01-2.29). CONCLUSIONS: Non-atopic wheezing was associated with risk factors indicative of poverty, dirt and infections. Further research is required to more precisely define the mediating exposures and the mechanisms by which they may cause non-atopic wheeze.
Assuntos
Asma/epidemiologia , Higiene , Hipersensibilidade Imediata/epidemiologia , Sons Respiratórios , Infecções Respiratórias/epidemiologia , População Urbana/estatística & dados numéricos , Brasil/epidemiologia , Criança , Pré-Escolar , Comorbidade , Feminino , Humanos , Masculino , Áreas de Pobreza , Prevalência , Medição de Risco , Fatores de RiscoRESUMO
BACKGROUND: Many epidemiologic studies report the odds ratio as a measure of association for cross-sectional studies with common outcomes. In such cases, the prevalence ratios may not be inferred from the estimated odds ratios. This paper overviews the most commonly used procedures to obtain adjusted prevalence ratios and extends the discussion to the analysis of clustered cross-sectional studies. METHODS: Prevalence ratios(PR) were estimated using logistic models with random effects. Their 95% confidence intervals were obtained using delta method and clustered bootstrap. The performance of these approaches was evaluated through simulation studies. Using data from two studies with health-related outcomes in children, we discuss the interpretation of the measures of association and their implications. RESULTS: The results from data analysis highlighted major differences between estimated OR and PR. Results from simulation studies indicate an improved performance of delta method compared to bootstrap when there are small number of clusters. CONCLUSION: We recommend the use of logistic model with random effects for analysis of clustered data. The choice of method to estimate confidence intervals for PR (delta or bootstrap method) should be based on study design.
Assuntos
Estudos Transversais , Prevalência , Criança , Análise por Conglomerados , Simulação por Computador , Estudos Epidemiológicos , Humanos , Modelos Logísticos , Razão de ChancesRESUMO
PURPOSE: Metabolic syndrome (MS) is a clustering of cardiovascular disease risk factors that identifies individuals with the highest risk for heart disease. Two factors that may influence the MS are physical activity and aerobic fitness. This study determined if adolescent with the MS had low levels of aerobic fitness and physical activity as children. METHODS: This longitudinal, exploratory study had 389 participants: 51% girls, 84% Caucasian, 12% African American, 1% Hispanic, and 3% other races, from the State of North Carolina. Habitual physical activity (PA survey), aerobic fitness (VO2max), body mass index (BMI), blood pressure, and lipids obtained at 7-10 y of age were compared to their results obtained 7 y later at ages 14-17 y. RESULTS: Eighteen adolescents (4.6%) developed 3 or more characteristics of the MS. Logistic regression, adjusting for BMI percentile, blood pressure, and cholesterol levels, found that adolescents with the MS were 6.08 (95%CI = 1.18-60.08) times more likely to have low aerobic fitness as children and 5.16 (95%CI = 1.06-49.66) times more likely to have low PA levels. CONCLUSION: Low levels of childhood physical activity and aerobic fitness are associated with the presence of the metabolic syndrome in adolescents. Thus, efforts need to begin early in childhood to increase exercise.
RESUMO
OBJECTIVE: This study investigates the association between personal-level and group-level discrimination and common mental disorders (CMDs) among Afro-Brazilian women, aiming to explore the role of skin color on this association. METHODS: This is a cross-sectional study involving 1130 women who were participating in the Social Change, Asthma and Allergy in Latin America (SCAALA) study, whose children were recruited from 24 geographical micro-regions representative of the population without sanitation. Measures of discrimination were defined by: experiences (personal-level) and concern about discrimination (group-level) using the Experiences of Discrimination Scale. Skin color was registered by self-declaration, being classified as white, brown, and black. The association between "self-reported" discrimination and CMDs was evaluated using Poisson regression analysis. RESULTS: Prevalence of CMDs was high (38.3%), especially in the group exposed to discriminatory experiences and black women. Experiences and concern about discrimination were positive and significantly associated with mental health, before and after adjustment for potential confounders. The effect of discrimination on CMDs was lower among black women, suggesting the development of other strategies to confront racism. CONCLUSION: This study emphasizes the use of both personal- and group-level discrimination measures, as well as skin color, for the evaluation of mental disorders in public health research. Further studies of health consequences of discrimination will require investigation of protective factors for mental disorders in the population suffering discrimination and racism.
Assuntos
Ansiedade/psicologia , População Negra/psicologia , Depressão/psicologia , Racismo/psicologia , População Branca/psicologia , Adaptação Psicológica , Adulto , Ansiedade/epidemiologia , População Negra/estatística & dados numéricos , Brasil/epidemiologia , Depressão/epidemiologia , Feminino , Humanos , Transtornos Psicofisiológicos/epidemiologia , Transtornos Psicofisiológicos/psicologia , Racismo/estatística & dados numéricos , Pigmentação da Pele , Transtornos Somatoformes/epidemiologia , Transtornos Somatoformes/psicologia , População Branca/estatística & dados numéricosRESUMO
Objective: To analyze the prevalence of common mental disorders (CMD) assessed with the Self Reporting Questionnaire (SRQ-20), using the established cutoff point, and comparing it with the results of a joint correspondence factor analysis (CFA) and cluster analysis and of a latent class analysis (LCA). Methods: A cross-sectional study was carried out in an urban sample of 1,095 women aged 19 to 55 years. Joint CFA-cluster analysis and LCA were used. Results: We found a high prevalence of CMD, regardless of classification method (37.6% when using the cutoff point; 44.4% and 52% for LCA and joint CFA-cluster, respectively). The alternative analysis strategies describe the cases more efficiently when compared to the traditional cutoff method, especially regarding more severe symptoms. Both alternative strategies also provide a description of the SRQ-20 dimensions in their particularities, which may be useful for the planning and implementation of specific actions in a given population. Conclusion: The SRQ-20 cutoff point seems to underestimate the magnitude of CMD among women. The alternative methods of analysis presented herein highlight the different possibilities of using this important instrument of screening for mental health.
Assuntos
Transtornos Mentais/diagnóstico , Adulto , Idoso , Brasil/epidemiologia , Estudos Transversais , Análise Fatorial , Feminino , Humanos , Transtornos Mentais/epidemiologia , Pessoa de Meia-Idade , Prevalência , Escalas de Graduação Psiquiátrica , Autorrelato , Fatores Socioeconômicos , Inquéritos e Questionários , População UrbanaRESUMO
Abstract Studies analyzing relations between cardiovascular diseases (CVDs) and environmental aspects in Latin American cities are relatively recent and limited, since most of them are conducted in high-income countries, analyzing mortality outcomes, and comprising large areas. This research focuses on adults with diabetes and/or hypertension under clinical follow-up who live in deprived areas. At the individual level we evaluated sociodemographic and cardiovascular risk factors from patient's records, and at the neighborhood level, socioeconomic conditions from census data. A multilevel analysis was carried out to study CVD. More women than men were under clinical follow-up, but men had higher frequency, higher odds, and shorter time to CVD diagnosis. Multilevel analysis showed that residing in neighborhoods with worst socioeconomic conditions leads to higher odds of CVDs, even after controlling for individual variables: OR (CI95%) of CVD in quartile 2 (Q2) 3.9 (1.2-12.1); Q3 4.0 (1.3-12.3); Q4 2.3 (0.7-8.0) (vs. highest socioeconomic level quartile). Among individuals living in unequal contexts, we found differences in CVD, which makes visible inequalities within inequalities. Differences between women and men should be considered through a gender perspective.
Resumo Os estudos que analisam as relações entre doenças cardiovasculares (DCVs) e aspectos ambientais em cidades latino-americanas são relativamente recentes e limitados. A maioria é realizada em países de alta renda analisando a mortalidade em grandes áreas. Esta investigação foca a população de adultos em acompanhamento clínico por diabetes e/ou hipertensão residentes em áreas carentes. No nível individual foram avaliados fatores sociodemográficos e de risco cardiovascular a partir dos prontuários médicos; e a partir de dados censitários, as condições socioeconômicas no nível da vizinhança. Mais mulheres do que homens estavam sob acompanhamento clínico, mas os homens apresentaram maior frequência, maior chance e menor tempo para diagnóstico de DCV. A análise multinível mostrou que residir em bairros com piores condições socioeconômicas leva a maiores chances de DCV, mesmo após o controle de variáveis individuais. As OR (IC95%) de DCV foram: Q2 OR 3,9 (1,2-12,1); Q3 OR 4,0 (1,3-12,3); Q4 OR 2,3 (0,7-8,0) (referência: quartil de maior nível socioeconômico). Entre os indivíduos que vivem em contextos desiguais, encontramos diferenças nas DCV, mostrando desigualdades dentro das desigualdades. Diferenças entre homens e mulheres devem ser abordadas com uma perspectiva de gênero.
RESUMO
The first years of life are the most dynamic period for childhood growth. There are limited data available on growth patterns of infants and children living in rural Latin America. The aim of this study was to describe the growth patterns from birth to 5years in children living in a rural District of tropical coastal Ecuador using data from a birth cohort of 2404 neonates. We hypothesize that there would be growth differences according to ethnicity and sex. Evaluations were conducted at birth or until 2weeks of age and at 7, 13, 24, 36 and 60months during clinic and home visits. Individual growth trajectories for weight-for-age, height-for-age and weight/height-for-age Z-scores were estimated using multilevel models. Girls were lighter and shorter than boys at birth. However, Afro-Ecuadorian children (versus mestizo or indigenous) were longer/taller and heavier throughout the first 5years of life and had greater mean trajectories for HAZ and WAZ independent of sex and socioeconomic factors. Our data indicate that ethnicity is a determinant of growth trajectories during the first 5years of life independent of socioeconomic factors in a birth cohort conducted in a rural region of Latin America.